This will be a single centre prospective experimental study, involving seven orthopaedic surgeons and their patients undergoing total knee replacement (TKR). A consecutive sample of elective primary TKR patients will be invited to participate from London Health Sciences Centre, University Hospital, London, Ontario, Canada. Additionally, patient hospital charts will be accessed to establish the concordance between co-morbidities recorded in patient history and self-report measures of co-morbidities.